Zend DBi is based on MariaDB with care and support for IBMi. It is a drop-in replacement for MySQL on many systems.
Zend DBi is built in Zend Labs from MariaDB source code, and fully tested on IBM i using Zend Server.
Zend DBi provides the same capabilities which are so familiar to LAMP developers (LAMP being Linux Apache MySQL/MariaDB and PHP), in the IBM i environment.
Zend DBi provides a fully supported and reliable Application Database Backend, for Zend Server PHP and any other MariaDB client which is connecting from an IBM i machine or remotely into the database.
From MariaDB website:
MariaDB Server is one of the most popular database servers in the world. It’s made by the original developers of MySQL and guaranteed to stay open source. Notable users include Wikipedia, WordPress.com and Google.
Read more about MariaDB on MariaDB official page